Laser machining apparatus, and apparatus and method for manufacturing a multilayered printed wiring board

ABSTRACT

There is provided a laser processing apparatus, a multilayer printed wiring board manufacturing apparatus, and a manufacturing method to form via holes of ultra-fine diameter. The laser beam from the CO 2  laser oscillator ( 60 ) is converted to the shortened wavelength beam by a tellurium crystal ( 94 ) to control diffraction of the laser beam. Simultaneously, when the laser beam is condensed, a limit value of the condensation limit is reduced. Thereby, the spot diameter of laser beam is reduced and a hole for via hole is bored on the interlayer insulation resin on a substrate ( 10 ). Therefore, even when the laser beam output is raised to form a deeper hole, the hole diameter is not widened and thereby a hole for a small diameter via hole can be formed.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a multilayer printed wiringboard manufacturing apparatus and method and a laser processingapparatus, particularly to a multilayer printed wiring boardmanufacturing apparatus and method to form fine holes at a low cost anda laser processing apparatus.

[0003] 2. Description of Related Art

[0004] A build-up multilayer wiring, board alternately has interlayerresin insulators and conductive circuit layers, provides holes to theinterlayer resin insulator layers and then electrically connects theupper layers and lower layers by forming conductive films at the wallsurface of these holes.

[0005] A hole (via hole) of the interlayer resin insulating layer isgenerally formed through the exposure and developing process by givingphotosensitive property to the interlayer resin.

[0006] However, the diameter of these via holes on the multilayerprinted wiring board is almost 100 μm or less and it is expected todevelop the technology to form the via hole having still smallerdiameter. Because of such requirement, employment of the processingmethod utilizing the laser beam for the boring of the build-upmultilayer wiring board is now investigated.

[0007] A technology using laser for the boring is proposed, for example,in the Japanese Published Examined Patent No. HEI 3-54884. In thistechnology, a light beam from the laser source is received by aprocessing head for deflection. Thereby the laser beam is irradiated toa predetermined resin insulator to form a through hole.

[0008] However, a multilayer wiring board has via holes in one layer inthe number ranging from several hundreds to several tens of hundred andis also required to have higher positional accuracy because the viaholes must be electrically connected with conductive circuits of thelower layer. Therefore, it has been required to enable the positioningof laser with higher accuracy in order to realize mass-production of themulti layer printed wiring board.

[0009] Namely, it is required to accurately measure the substrateposition to embody the automatic control for mass production.

[0010] As a method of measuring the substrate position, an ordinarymethod has been introduced in which a positioning mark provided on thesubstrate is read with a camera to measure the position.

[0011] However, in the case of a multilayer printed wiring board, thepositioning marks are often formed on a lower layer of the resin layerto be eliminated by a laser beam and if it is attempted to read thelight beam reflected from the positioning mark under the resin layer, itis sometimes difficult to accurately read the reflected beam throughreflection by the resin layer.

[0012] Therefore, the inventors of the present invention has proposed,as a method of accurately reading the positioning mark, to read thepositioning mark from a silhouette by making use of the transmittinglight beam of the light applied to the multilayer printed wiring boardfrom the lower side.

[0013] However, since the multilayer printed wiring board is placed onan X-Y table, when the light is applied to the substrate from the lowerside, it is thought that the table itself or a driver motor for drivingthe table will interfere the application of light beam.

[0014] Moreover, since the substrate is always moving by means of theX-Y table, it is also difficult to always apply the light beam from thelower side of the positioning mark which moves in combination with theX-Y table. Moreover, a problem like this arises not only in the multilayer printed wiring board but also in automatic laser process.

[0015] On the other hand, in order to bore the via holes and throughholes of the multi layer printed wiring board, a laser beam-in such awavelength as generating heat in the interlayer resin must be used andthe CO₂ laser or excimer laser are considered as such laser source. Theexcimer laser has the wavelength as short as 248 nm in KrF, 308 nm inXeCL and 193 nm in ArF are and is suitable for formation of a smalldiameter via hole.

[0016] However, the excimer laser results in rise of product cost, whenit is introduced into the industrial use, because the apparatus costbecomes high, and further parts such as lens are easily deterioratedbecause of short wavelength and these parts must be replaced frequently,and the expensive excimer gas must be supplemented and replaced within ashort period.

[0017] Regarding this point, the CO₂ laser having a relatively longerwavelength is rather suitable for industrial use because not only outputlevel is high and the apparatus cost is low but also repair of lens, forexample, is not required and supplement of CO₂ laser can be realized ata low price, however when laser beam output is raised to form a deeperhole, hole diameter of via-hole becomes larger. In addition, the hole indiameter of 100 μm which is about 10 times the wavelength (10.6 μm) canbe bored easily but the hole in diameter of 50 μm or less which is about5 times the wavelength is bored with considerable difficulty.

[0018] Such problem is generated also when the CO₂ laser is used as thelaser source for processing, in addition to the multilayer printedwiring board.

[0019] Moreover, in the manufacturing apparatus of a multilayer printedwiring board of the related art, since several thousands to several tensof thousand via holes are bored in the multi layer printed wiring board,a longer time has been required to bore the holes of only one layer withthe laser and the processing time becomes very long when such laserprocess is repeated for multiple layers.

[0020] It is an object of the present invention to provide an apparatusand a method of manufacturing a multilayer printed wiring board which,while securing the position accuracy of via holes, bore hundreds orthousands of holes by use of laser beam radiation.

[0021] It is therefore another object of the present invention toprovide an apparatus and a method of manufacturing a multilayer printedwiring board which can form via holes of ultra-fine diameter at a lowcost and also provide a laser processing apparatus which can form holesof ultra-fine diameter.

[0022] It is another object of the present invention to provide a laserprocessing apparatus, an apparatus and a method of manufacturing amultilayer printed wiring board which can read accurately thepositioning marks.

[0023] It is further another object of the present invention to providea laser processing apparatus which, can reduce the processing time.

[0024] Moreover, it is still further another object of the presentinvention to provide an apparatus and a method of manufacturing amultilayer printed wiring board which can reduce the time required toform the via holes of a built-up type multilayer printed wiring board.

DISCLOSURE OF THE INVENTION

[0025] In order to attain the objects explained above, an apparatus ofmanufacturing a multilayer printed wiring board of claim 1 ischaracterized from the technical viewpoint that:

[0026] it is used for processing a multilayer printed wiring boardhaving an interlayer resin insulator;

[0027] it comprises a processing laser source, a scanning head fordeflecting the direction of laser beam toward the X-Y directions, acamera to read the positioning marks of the multilayer printed wiringboard, an X-Y table for placing the multilayer printed wiring board, aninput section for inputting the processing data of the multilayerprinted wiring board, a memory section for storing the processing dataor the arithmetic operations result, and an arithmetic operatingsection;

[0028] the processing data is input from the input section and this datais then stored in the memory section;

[0029] the positions of the positioning marks of the multilayer printedwiring board placed on the X-Y table is measured with the camera;

[0030] the processing data input on the basis of the measured positionis corrected to generate the data to drive the scanning head and the X-Ytable in the arithmetic operating section and this driver data is thenstored in the memory section; and

[0031] the drive data is read from the memory section in the controlsection and the laser beam is radiated to the multilayer printed wiringboard by controlling the X-Y table and the scanning head to form theholes by eliminating the interlayer resin layer.

[0032] In order to attain the objects described above, the method ofmanufacturing a multilayer printed wiring board of claim 4 ischaracterized from the technical view point in comprising the steps of:

[0033] forming the positioning marks and interlayer insulating layer onthe multilayer printed wiring board;

[0034] placing the multilayer printed wiring board having formed thepositioning marks on the X-Y table of the multilayer printed wiringboard manufacturing apparatus comprising the processing laser source,the scanning head for deflecting the direction of laser beam to the X-Ydirections the camera for reading the positioning marks on themultilayer printed wiring board, the X-Y table for placing themultilayer printed wiring board, the input section for inputting theprocessing data of the multilayer printed wiring board, the memorysection for storing the processing data or the arithmetic operationsresult and the arithmetic operating section and also inputting theprocessing data to this apparatus;

[0035] measuring the positions of the positioning marks on themultilayer printed wiring board with the camera, correcting the inputprocessing data based on the measured positions of the positioning marksin the arithmetic operating section to generate the data for driving thescanning head and X-Y table and storing this drive data to the memorysection; and

[0036] reading the drive data from the memory section in the controlsection radiating the laser beam to the multilayer printed wiring boardby controlling the X-Y table and the scanning head to eliminate theinterlayer resin layer in order to form the holes.

[0037] In the present invention, since position of the positioning markis measured with a camera to actually measure the position of thesubstrate by forming in advance the positioning mark at thepredetermined position of the multilayer printed wiring board, theposition of the substrate is measured, and deviation of the substrateposition is corrected from the input processing data and actuallymeasured value of the substrate to generate the scanning head and X-Ytable drive data. Thereby, the scanning head and the X-Y table aredriven depending on this drive data. As a result, boring of many viaholes of several hundreds to several tens of hundred can be realizedwhile keeping the higher positional accuracy.

[0038] In the present invention, it is desirable that the positioningmark of the multilayer printed wiring board is formed of a metalconductor. It is because when the mark is read with the beam reflectedfrom the positioning mark, a metal assures a higher reflectivity and itmay be easily read by the camera. Moreover, in the case where thepositioning mark is read with the transmitting light beam, since themetal does not transmit the light beam, the positioning mark can berecognized by a silhouette and can easily be read by the camera.

[0039] Moreover, it is also desirable that the positioning mark isformed simultaneously with a conductive circuit, because it is notrequired, in this case, to additionally provide the process to form thepositioning mark.

[0040] Specifically, at the time of forming a conductor pattern byetching a copper clad laminated plate, the positioning marks may beformed. Moreover, a plating resist is provided at the conductor circuitand the positioning mark non-forming area and thereby the conductivecircuit and the positioning mark can be formed simultaneously by theplating.

[0041] As explained above, when the conductor circuit and positioningmark are formed simultaneously, it is desirable to use an interlayerresin insulator having a light transmissivity because the positioningmark is covered with the interlayer resin insulator.

[0042] The inventors of the present invention have made efforts toinvestigation to find a cause of increase in diameter of the via holes,etc. As a result, it has been proved that the CO₂ laser has thewavelength as long as 10.6 μm the spot diameter becomes large when thelight is focused due to the influence of diffraction of laser beam andwhen an output is increased, the hole diameter becomes larger than thepreset value.

[0043] Therefore, it has also been found that diffraction of laser beamcan be control led and the spot diameter when the light beam is focusedcan be set as small as possible to form the via hole having the smalldiameter when the laser beam has a longer wavelength.

[0044] The present invention has been proposed based on such finding andthereby the apparatus for manufacturing the multilayer printed wiringboard described in claim 5 discloses a multilayer printed wiring boardmanufacturing apparatus comprising a CO₂ laser source, a scanning headfor deflecting the direction of the laser beam to the X-Y directions oran X-Y table for displacing the position of the multilayer printedwiring board and is characterized in the technical view point by thatthe laser beam oscillated from the CO₂ laser source is given theshortened wavelength by a harmonic wave generating means.

[0045] Moreover, the multilayer printed wiring board manufacturingapparatus described in claim 6 discloses a multilayer printed wiringboard manufacturing apparatus comprising a processing laser source, aharmonic wave generating means for converting the laser beam oscillatedfrom the processing laser source to a shortened wavelength laser beam inthe second harmonic wave, a scanning head for deflecting the directionof the laser beam toward the X-Y directions or an X-Y table fordisplacing the position of the multilayer printed wiring board and isalso characterized from the technical view point by that the wavelengthof the processing laser source is ranged from 720 nm or less to theshortest wavelength or more of the laser source or from 6000 nm or moreto the maximum wavelength or less of the laser source.

[0046] Moreover, the multilayer printed wiring board described in claim7 comprises:

[0047] a CO₂ laser source, a scanning head for deflecting the directionof laser beam to the X-Y directions, a camera for reading the targetmark on the multi layer printed wiring board, an X-Y table for placingthe multilayer printed wiring board, an input section for inputting theprocessing data of the multilayer printed wiring board, a memory sectionfor storing the processing data or the arithmetic operations result andan arithmetic operating section in order to:

[0048] input the processing data from the input section to store it tothe memory section;

[0049] measure, with the camera, the position of the target mark of themultilayer printed wiring board placed on the X-Y table:

[0050] generate, in the arithmetic operating section, the data fordriving the scanning head and the X-Y table from the measured positionand the input processing data and then store this data to the memorysection;

[0051] read, in the control section, the drive data from the memorysection and radiate the laser beam to the multilayer printed wiringboard by controlling the X-Y table and the scanning head to eliminatethe interlayer resin layer in order to form the hole; and is alsocharacterized in the technical view point by that the laser beamoscillated from the CO₂ laser source is converted to the shortenedwavelength beam in the second harmonic wavelength by the harmonic wavegenerating means.

[0052] Moreover, the multilayer printed wiring board manufacturingmethod described in claims 10 discloses a multilayer printed wiringboard manufacturing method using a manufacturing apparatus comprising aCO₂ laser source, a harmonic wave generator for converting the laserbeam from the CO₂ laser source to the shortened wavelength in secondharmonic wave, a scanning head for deflecting the direction of laserbeam to the X-Y direction, a camera for reading the target mark of themultilayer printed wiring board and an X-Y table for placing themultilayer printed wiring board and is characterized in the technicalview point in comprising the steps of:

[0053] measuring the position of the target mark of the multilayerprinted wiring board having the interlayer resin insulator placed on theX-Y table;

[0054] generating the data for driving the scanning head and the X-Ytable from the measured position and the processing data: and

[0055] eliminating the interlayer resin layer and forming holes bycontrolling the Y-Y table and the scanning head based on the drive dataand radiating the shortened wavelength laser beam in the second harmonicwave from the harmonic wave generator to the multilayer printed wiringboard.

[0056] The present invention converts the laser beam from the lasersource to the shortened wavelength wave by the harmonic wave generatingmeans to control the diffraction of laser beam and also can reduce thespot diameter of laser beam, when the laser beam is focused, by makingsmall the limit value of the focusing limit. As a result, when an outputof the laser beam is raised to form a deeper hole, the hole diameter isnot widened. Therefore, the via hole and small diameter hole can also beformed.

[0057] As the laser source explained above, the CO₂ gas is desirablebecause the apparatus is low price and provides an high output andassures also a lower running cost.

[0058] As the harmonic wave generating means, a waveguide or a bulk ofnon-linear optical crystal may be used.

[0059] Specifically, a means for reflecting the laser beam from the CO₂laser source and for transmitting the harmonic generated by non-linearoptical crystal is provided in the harmonic wave output side of thenon-linear optical crystal. The laser beam of the light sourcewavelength is reflected and the shortened wavelength laser beam istransmitted in direct. Thereby, the processing is executed only by theshortened wavelength laser beam.

[0060] As the means for reflecting the laser beam from the processinglaser source and transmitting the harmonic generated by the non-linearoptical crystal, a thin film (coating), for example, of sodium fluorideis formed on the surface of collimator lens.

[0061] Here, it is recommended to provide the function for totallytransmitting the laser beam from the processing laser source on theincident side of the non-linear optical crystal, namely in theprocessing laser source side for the purpose of improving the input andoutput efficiency of light beam.

[0062] On the incident side of the non-linear optical crystal, the thinfilm of sodium fluoride and silicon, etc. in which the number of layersand thickness are adjusted is formed at the surface of the condenserlens and the end face of the non-linear optical crystal as the means forgiving the function to totally transmit the laser beam from theprocessing laser source.

[0063] Moreover, it is also allowed that the non-linear optical crystalis provided within the laser source and the function for reflecting apart of the laser beam of the light source wavelength is provided on theincident side of the non-linear optical crystal or a resonator is formedwithin the processing laser source using a half-mirror. It is becausethe resonator type harmonic wave generator assures high conversionefficiency and also practical use and moreover higher conversionefficiency can also be obtained by giving a higher output to non-linearoptical crystal.

[0064] As the non-linear optical crystal, tellurium is preferable. TheCO₂ laser which is optimum as the laser source assures the far infraredband and realizes the phase matching of the wavelength of this band.

[0065] When tellurium is used, the cutting angle for the c-axis isdetermined to θ=14.30 in order to realize the phase matching for the CO₂laser.

[0066] Wavelength of the CO₂ laser is 10.6 μm and the second harmonicgenerated has the wavelength of 5.3 μm. Therefore, the hole in diameterof 50 μm which is about 10 time the second harmonic can easily beformed.

[0067] Here, in order to bore the hole on the interlayer resininsulator, wavelength must be 360 nm or less or 3000 nm or more.Therefore, the wavelength of the processing laser source assuringshortened wavelength of the second harmonic wave must be 720 nm or lessor 6000 nm or more.

[0068] The present invention is particularly effective to form the holewhere the aspect ratio (depth of hole/diameter of hole) is 1.5 or less.

[0069] In order to attain the object explained above, the multilayerprinted wiring board manufacturing apparatus described in claim 13 ischaracterized in the technical viewpoint by that:

[0070] it is used for processing the multilayer printed wiring boardhaving the interlayer resin insulator;

[0071] it comprises a processing laser source, a scanning head fordeflecting the direction of laser beam to the X-Y directions, a camerafor reading the positioning mark of the multilayer printed wiring board,an X-Y table for placing the multilayer printed wiring board, an inputsection for inputting the processing data of the multilayer printedwiring board, amemory section for storing the processing data or thearithmetic operations result and an arithmetic operating section: and

[0072] the X-Y table is provided with the embedded light source at thearea corresponding to the positioning mark of the multilayer printedwiring board.

[0073] Moreover, the multilayer printed wiring board manufacturingapparatus described in claim 14 is characterized in the technicalviewpoint by that:

[0074] it is used for processing the multilayer printed wiring boardhaving an interlayer resin insulator;

[0075] it comprises a processing laser source, a scanning head fordeflecting the direction of the laser beam to the X-Y directions, acamera for reading the positioning mark of the multilayer printed wiringboard, an X-Y table for placing the multilayer printed wiring board, aninput section for inputting the processing data of the multilayerprinted wiring board, a memory section for storing the processing dataor the arithmetic operations result and an arithmetic operating section;

[0076] the X-Y table is provided with an embedded light source at thearea corresponding to the positioning mark of the multilayer printedwiring board;

[0077] the processing data is input from the input section and it isthen stored in the memory section;

[0078] a silhouette, which is formed when the light beam from the lightsource of the X-Y table is shielded by the positioning mark, is read bythe camera and the position of the positioning mark of the multilayerprinted wiring board placed on the X-Y table is measured;

[0079] the data for driving the scanning head and the X-Y table isgenerated from the measured position and the input processing data inthe arithmetic operating section and this drive data is then stored inthe memory section; and

[0080] the drive data is read from the memory section in the controlsection to control the X-Y table and the scanning head and the laserbeam is then radiated to the multilayer printed wiring board toeliminate the interlayer resin layer in order to form a hole.

[0081] In order to attain the object described above, the multilayerprinted wiring board manufacturing method described in claim 16discloses the multilayer printed wiring board manufacturing methodutilizing a manufacturing apparatus comprising a processing lasersource, a scanning head for deflecting the direction of laser beam tothe X-Y directions, a camera for reading the positioning mark of themultilayer printed wiring board and an X-Y table for placing themultilayer printed wiring board and also providing the light sourceembedded to the area corresponding to the positioning mark of themultilayer printed wiring board and is characterized in the technicalviewpoint by comprising the steps of:

[0082] forming the positioning mark and interlayer resin insulator onthe multilayer printed wiring board;

[0083] inputting the processing data to the manufacturing apparatus;

[0084] reading a silhouette, with the camera, which is formed when thelight beam from the light source of the X-Y table is shielded by thepositioning mark of the multilayer printed wiring board and measuringthe position of the positioning mark of the multilayer printed wiringboard;

[0085] generating the data for driving the scanning head and the X-Ytable from the measured position and the input processing data; and

[0086] radiating the laser beam to the multilayer printed wiring boardby controlling the X-Y table and the scanning head on the basis of thedrive data to eliminate the interlayer resin layer in view of formingthe hole.

[0087] The laser processing apparatus described in claim 19 ischaracterized in the technical viewpoint by comprising a processinglaser source, a scanning head for deflecting the direction of the laserbeam to the X-Y directions, a camera for reading the positioning mark ofa work piece to be processed, an X-Y table for placing the work piece tobe processed, an input section for inputting the processing data of thework piece to be processed, a memory section for storing the processingdata or the arithmetic operations result and an arithmetic operatingsection and is also characterized in providing a light source at thearea of the X-Y table corresponding to the positioning mark of the workpiece to be processed.

[0088] The inventors of the present invention have completed the presentinvention, as a result of investigation, by finding that the light beamcan be always applied from the lower side of the positioning mark,without any interference of the X-Y table itself or the drive motor, byembedding the light source at the position corresponding to thepositioning mark of the X-Y table.

[0089] In the present invention, when a work piece to be processed suchas a multilayer printed wiring board is placed on the X-Y table, sincethe light source is embedded to the area corresponding to the positionmark of the work piece to be processed such as the multilayer printedwiring board, the positioning mark is recognized as a silhouette becausethe light from the light source is shielded by the positioning mark ofthe work piece to be processed such as the multilayer printed wiringboard and it is then read by the camera. This silhouette is notinfluenced by the gloss of a resin layer even when the positioning markis provided at the lower layer of the resin layer to be eliminated bythe laser. Moreover, the since the light source is embedded in the X-Ytable itself, the light source is never shielded by the X-Y table or thedrive motor, and since the light source moves together with the X-Ytable, the light can always be applied from the lower side of thepositioning mark and the positioning mark can always be recognized evenwhen the X-Y table moves.

[0090] In addition, since it is enough that the light source radiatesonly the positioning mark area, the light source area and amount oflight can be reduced and thereby the substrate is never warped and thework piece such as substrate is never changed in size by the heat fromthe light source.

[0091] Moreover, since the light source area can be reduced, a grooveand a hole can be provided to the X-Y table for the purpose of vacuumabsorption and the substrate can surely be fixed.

[0092] As the light source used in the present invention, an LED (LightEmitting Diode), a laser source, a fluorescent light or a small sizebulb may be listed. The LED is most preferable because it is small andlight, therefore it does not increase an inertia of the X-Y table,assuredly realizing a small amount of heat generation and highluminance. In addition, it is suitable for mass-production of theprinted wiring board because it assures a longer exchange time. As thecolor of light emitted by this LED, green which may be recognized by CCDas the image pickup element of camera is preferable.

[0093] As a structure of the light source, an aperture is provided tothe X-Y table and the light source such as LED and a socket to beconnected to the light source are embedded in this aperture. The socketis connected to the cable wired at the inside or rear surface of the X-Ytable and this cable is then connected to the external power supply.

[0094] A rectangular shape is the most preferable for the aperture. Thepositioning mark is formed for each insulator layer and therefore theseare never overlapped with each other. Moreover, the apertures are formedin lateral on a line while the positioning mark of each layer isdeviated. Since the aperture is formed in the rectangular shape, thepositioning mark of each layer can be radiated simultaneously with thelight beam.

[0095] In the present invention, since the positioning mark is formed inadvance at the predetermined position of the work piece such asmultilayer printed wiring board, the position of the work piece such assubstrate is measured actually by measuring the position of silhouetteof the positioning mark with a camera, the data for driving thegalvano-mirror and X-Y table is generated to compensate for deviation ofthe substrate position from the input processing data and theactually-measured value of the substrate position and the galvano-mirrorand X-Y table are driven depending on this drive data. Thereby, it ispossible to realize the boring of many via holes ranging from severalhundreds to several tens of hundred while keeping the higher positionalaccuracy.

[0096] In the present invention, it is preferable that the positioningmark of the multilayer printed wiring board is made of a metalconductor. Since a metal does not transmit the light beam, thepositioning mark can be recognized by a silhouette and it can easily beread with the camera.

[0097] Moreover, the positioning mark is preferably formedsimultaneously with the conductive circuit because it is not required,in this case, to additionally provide the positioning mark formingprocess.

[0098] At the time of forming the positioning mark on the multilayerprinted wiring board, it is desirable that the positioning mark of theupper layer is deviated from the positioning mark of the lower layer.Thereby, the silhouette of the positioning mark of the upper layer isnever overlapped on the positioning mark of the lower layer.

[0099] Specifically, the positioning mark can be formed on the occasionof forming the conductor pattern by etching the copper clad laminatedplate. Moreover, a plating resist is provided in advance on the areawhere the conductive circuit and positioning mark are not provided andthereby the conductive circuit and positioning mark can be formedsimultaneously through the plating process.

[0100] When the conductive circuit and positioning mark are formedsimultaneously, the positioning mark is covered with the interlayerresin insulator. Therefore it is preferable to use a material having thelight transmitting property as the interlayer resin insulator. Inaddition, it is also preferable to use a material having the lighttransmitting property for the substrate itself on which the interlayerresin insulator is formed.

[0101] In order to attain the object described above, the laserprocessing apparatus described in claim 20 discloses laser processingapparatus comprising a processing laser source, a scanning head fordeflecting the direction of laser beam to the X-Y directions and an X-Ytable for placing the work piece to process the work piece with a laserbeam by controlling the X-Y table and the scanning head, characterizedin the technical viewpoint by providing at least two or more scanningheads and a beam splitter between the processing laser source and anoptical path of the scanning head to supply the laser beam to eachscanning head by distributing the laser beam.

[0102] Moreover, the multilayer printed wiring board manufacturingapparatus described in claim 21 discloses, in order to attain the objectexplained above, a multilayer printed wiring board which is used forprocessing a multilayer printed wiring board having an interlayer resininsulator and comprises a processing laser source, a scanning head fordeflecting the direction of laser beam to X-Y directions, a camera forreading the target mark of the multilayer printed wiring board, an X-Ytable for placing the multilayer printed wiring board, an input sectionfor inputting the processing data of the multilayer printed wiringboard, a memory section for storing the processing data or thearithmetic operations result and an arithmetic operating section toinput the processing data from the input section, stores this data tothe memory section, measures the position of target mark of themultilayer printed wiring board placed on the X-Y table, generates thedata for driving the scanning head and the X-Y table from the measuredposition and the input processing data and stores this drive data to thememory section in the arithmetic operating section, reads the drive datafrom the memory section and radiates the laser beam to the multilayerprinted wiring board by controlling the X-Y table and the scanning headin the control section to eliminate the interlayer resin layer and formthe via hole, and this multilayer printed wiring board manufacturingapparatus is also characterized in the technical viewpoint by providingat least two or more scanning heads and a beam splitter between theprocessing laser source and an optical path of the scanning heads tosupply the laser beam to each scanning head by distributing the laserbeam with the beam splitter.

[0103] Moreover, the multilayer printed-wiring board manufacturingmethod described in claim 25 discloses a multilayer printed wiring boardmanufacturing method comprising the steps of:

[0104] forming the target mark on the multi layer printed wiring boardhaving the interlayer resin insulator;

[0105] placing the multilayer printed wiring board having formed thetarget mark on the X-Y table of the multilayer printed wiring boardmanufacturing apparatus comprising a processing laser source, at leasttwo or more scanning heads for deflecting the direction of laser beam tothe X-Y directions, a camera for reading the target mark of the multilayer printed wiring board, an X-Y table for placing the multilayerprinted wiring board, an input section for inputting the processing dataof the multilayer printed wiring board, a memory section for storing theprocessing data or the arithmetic operations result and an arithmeticoperating section and then inputting the processing data to thisapparatus;

[0106] measuring, in the arithmetic operating section, the position ofthe target mark of the multilayer printed wiring board with the camera,generating the data for driving the scanning head and the X-Y table fromthe measured position and the input processing data and storing thisdrive data in the memory section; and

[0107] reading the drive data from the memory section in the controlsection and radiating the laser beam to the multilayer printed wiringboard by controlling the X-Y table and the scanning head to eliminatethe interlayer resin layer to form the via hole; and

[0108] this method is characterized in the technical viewpoint bydistributing the laser beam with a beam splitter provided between theprocessing laser source and an optical path of the scanning head tosupply the laser beam to two or more scanning heads.

[0109] In the laser processing apparatus described in claim 20, themultilayer printed wiring board manufacturing apparatus described inclaim 21 and the multilayer printed wiring board manufacturing methoddescribed in claim 25, since the laser beam is distributed by the beamsplitter to supply the beam to a plurality of scanning heads even whenonly one laser source is provided, the boring velocity can be improvedeven when the apparatus size is not increased and thereby low cost laserboring can be realized. In addition, in the apparatus described inclaims 20, 21 and in the multi layer printed wiring board manufacturingmethod described in claim 25, processing and boring can be conducted toonly one work piece (multilayer printed wiring board) with two or morescanning heads. In this case the processing and boring time of the workpiece (multilayer printed wiring board) can be shortened and moreoverthe X-Y table area can be reduced to that of only one work piece(multilayer printed wiring board), thereby not resulting in increase insize of the apparatus as a whole.

[0110] In the preferred embodiment of the present invention, when a viahole is not formed with the other scanning head on the occasion offorming a via hole with the laser beam via one scanning head, the otherscanning head scans the outside of the processing area of the multilayerprinted wiring board with the laser beam. Therefore, it is possible toconduct the processing in different patterns with a plurality ofscanning heads.

[0111] In the preferred embodiment of the present invention, since atransfer mask is provided between the processing laser source and thebeam splitter, the structure can be more simplified than the structurewhere a plurality of masks are provided.

[0112] In the preferred embodiment of the present invention, since thetransfer mask is provided between the beam splitter and each scanninghead, the distance to the multilayer printed wiring board as theprocessing object from each transfer mask can be equalized.

BRIEF DESCRIPTION OF THE DRAWINGS

[0113]FIG. 1 is a schematic diagram of a multilayer printed wiring boardmanufacturing apparatus in relation to the first embodiment of thepresent invention;

[0114]FIG. 2 is a block diagram of a control mechanism of themanufacturing apparatus shown in FIG. 1;

[0115]FIG. 3 is a process diagram for the processing conducted by thecontrol mechanism shown in FIG. 2;

[0116]FIG. 4 is a process diagram for manufacturing a multilayer printedwiring board in relation to the first embodiment;

[0117]FIG. 5 is a process diagram for manufacturing a multilayer printedwiring board in relation the first embodiment;

[0118]FIG. 6 is a schematic diagram of a multilayer printed wiring boardmanufacturing apparatus in relation to a modification example of thefirst embodiment;

[0119]FIG. 7 is a schematic diagram of a multilayer printed wiring boardmanufacturing apparatus in relation to the second embodiment of thepresent invention;

[0120]FIG. 8 is a cross-sectional view along the line A-A of the X-Ytable shown in FIG. 7;

[0121]FIG. 9(A) is a plan view of an aperture of the X-Y table shown inFIG. 8, FIG. 9(B) is a cross-sectional view of the aperture, FIG. 9(C)is a plan view of the aperture, and FIG. 9(D) is a cross-sectional viewof the aperture;

[0122]FIG. 10 is a process diagram for manufacturing a multilayerprinted wiring board in relation to the second embodiment;

[0123]FIG. 11 is a process diagram for manufacturing a multilayerprinted wiring board in relation to the second embodiment;

[0124]FIG. 12 is a schematic diagram of a multilayer printed wiringboard in relation to the third embodiment of the present invention;

[0125]FIG. 13 is a block diagram of a control mechanism of themanufacturing apparatus shown in FIG. 12;

[0126]FIG. 14 is a process diagram of the processing by the controlmechanism shown in FIG. 13;

[0127]FIG. 15 is a flowchart of the galvano-data generating processshown in FIG. 14;

[0128]FIG. 16 is a schematic diagram of a multilayer printed wiringboard manufacturing apparatus in relation to a modification example ofthe third embodiment of the present invention; and

[0129]FIG. 17 is a schematic diagram of a multilayer printed wiringboard in relation to another modification example of the thirdembodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0130] The preferred embodiments of the present invention will beexplained below with reference to the accompanying drawings.

[0131]FIG. 1 shows a multilayer printed wiring board manufacturingapparatus in relation to the first embodiment of the present invention.

[0132] In the first embodiment, as the laser source, a CO₂ laseroscillator 60 which generates the CO₂ laser in the wavelength of 10.6 μmis used. This CO₂ laser oscillator 60 is designed as the resonator typeoscillator formed by sealing the CO₂ gas between a total reflectionmirror 60B and a partial reflection mirror 60A. An energy from theexcited CO₂ is emitted as the laser beam via the partial reflectionmirror 60A.

[0133] The laser beam in the beam diameter of 20 mm radiated from theCO₂ laser oscillator 60 is condensed by a condenser lens 92 of zincselenium (ZnSe) coated with a thin film of sodium fluoride (manufacturedby MELLES GRIOT) and is then incident to a metal tellurium 94. Thesurface of the condenser lens 92 is perfectly transmitting the lightbeam in the wavelength of 10.6 μm (AR: ANTIREFLECTION).

[0134] Tellurium 94 has the length of 5 mm and is cut in the angleθ=14.30 for the c-axis for the phase matching. The incident light in thewavelength of 10.6 μm is converted to the second harmonic wave in thewavelength of 5.3 μm by tellurium. The converted second harmonic wave isemitted from the tellurium crystal 94 and is then incident to thecollimator lens 90. The incident and emitting end faces of the telluriumcrystal 94 are coated with the thin film of sodium fluoride having theantireflection property for the beam in the wavelength of 10.6 μm inorder to improve the incident and emitting efficiency.

[0135] The second harmonic wave in the wavelength of 5.3 μm emitted fromtellurium 94 is paralleled by the collimator lens 90. The surface of thecollimator lens 90 (produced by MELLES GRIOT) is coated with a thin filmof sodium fluoride of which the number of layers and thickness areadjusted. This surface totally reflects (HR: Whole Reflection) the laserbeam having the wavelength of 10.6 μm and totally transmits (AR) thesecond harmonic wave having the wavelength of 5.3 μm. Namely, the laserbeam having the wavelength of 10.6 μm which is the unconverted lightsource wavelength is cut. Therefore, only the laser beam in thewavelength of 5.3 μm contributes to the processing.

[0136] The laser beam in the wavelength of 5.3 μm is reflected by amirror 66 of the optical system and is sent to the galvano-head 70 viathe transfer mask 62 to make clear the focal point on the substrate.

[0137] The galvano-head (scanning head) 70 is composed of a set of thegalvano-mirror formed of the galvano-mirror 74X for scanning the laserbeam in the X direction and the galvano-mirror 74Y for scanning the beamin the Y direction. These mirrors 74X, 74Y are driven by the controlmotors 72X, 72Y. The motors 72X, 72Y adjust the angles of the mirrors74X, 74Y depending on the control command from the computer to beexplained later and also transmits the detection signal from thebuilt-in encoder to the computer side.

[0138] The scan area of the galvano-mirror is 30×30 mm. Moreover, thepositioning velocity of the galvano-mirror is 400 points/sec within thescanning area. The laser beam is respectively scanned in the X-Ydirections through a couple of galvano-mirror 74X, 74Y and passes thef-θ lens 76 and collides with the bonding agent layer of the substrate10 to be explained later to form the via hole (aperture).

[0139] The substrate 10 is placed on the X-Y table 80 moving in the X-Ydirections. As explained above, since the scanning area ofgalvano-mirror of each galvano-head 70 is 30mm x 30mm and the substrate10 of 500 mm×500 mm is used, the number of step areas of the X-Y table80 is 289 (17×17). Namely, the processing of the substrate 10 can becompleted by repeating the movement of 30 mm in the X direction 17 timesand the movement in the Y direction 17 times, respectively.

[0140] The manufacturing apparatus explained above is also provided withthe CCD camera 82 and therefore the positions of the target marks(positioning marks) 11 arranged at four corners of the substrate 10 aremeasured to start the processing after compensating for the error.

[0141] Subsequently, the control mechanism of this manufacturingapparatus will be explained with reference to FIG. 2.

[0142] The control apparatus is formed of a computer 50 which receivesas an input the hole coordinate data (processing data) of the multilayerprinted wiring board input from the input section 54 and the position ofthe target mark 11 measured by the CCD camera 82 to generate theprocessing data to be stored in the memory section 52. The actual boringprocess can be conducted by driving the X-Y table 80, laser 60 and thegalvano-head 70 on the basis of the processing data.

[0143] Here, the processing data generating process by the computer 50will be explained in further detail with reference to FIG. 3.

[0144] The computer 50 drives first the X-Y table 80 to the position ofthe CCD camera 82 to move the target mark 11 (first process). Errorssuch as deviation in the X direction, deviation in the Y direction, acompression amount of substrate and an amount of rotation are measuredby catching the positions of the four target marks 11 with the CCDcamera 82 (second process). Here, an error data is generated forcorrecting the error of measurement (third process).

[0145] Subsequently, the computer 50 corrects the hole coordinate dataconsisting of the coordinates of respective holes with the error datagenerated in the third process to generate the actual processing dataconsisting of the coordinates of the holes actually bored (fourthprocess). On the basis of the actual processing data, the galvano-headdata for driving the galvano-head 70 is generated (fifth process), thetable data for driving the X-Y table is generated (sixth process), andthe laser data for the timing of oscillating the laser 60 is alsogenerated (seventh process). This data is temporarily stored in thememory section 52 as explained above and actual boring process isconducted by driving the X-Y table 80, laser 60 and galvano-head 70depending on this data.

[0146] Subsequently, the multilayer printed wiring board manufacturingprocess using the manufacturing apparatus in relation to the firstembodiment of the present invention will be explained with reference toFIG. 4 and FIG. 5.

[0147] First, using, as a starting material, a copper clad laminatedplate 10 a where the copper foil 12 of 18 μm is laminated on bothsurfaces of the substrate 10 consisting of glass epoxy or BT(bismaleimidetriazine) of 500×500 mm in the thickness of 1 mm shown inFIG. 4(A), the copper foil is etched in the form of a pattern by theordinary method as shown in the process (B) to form the internal layercopper patterns 14 a, 14 b and target marks 11 on both surfaces of thesubstrate 10.

[0148] Here, an interlayer resin insulator is prepared. After mixing thecresol novolak type epoxy resin (manufactured by Nippon Kayaku, Co.Ltd.: molecular weight 2500) of 70 parts by weight dissolved into DMDG(dimethylglicoldimethyethel), polyethelsulfone (FE) of 30 parts byweight, imidazole hardening agent (Shikoku Chemicals Corp.: Bland name2E4MZ-CN) of 4 parts by weight and then further mixing, with thismixture, the epoxy resin particle in average particle size of 5.5 μm of35 parts by weight and that in average particle size of 0 5 μm of 5parts by weight these are further kneaded while adding NMP to adjust theviscosity to 12 pa.s with a homogenizer and subsequently these arekneaded with three rolls to obtain the solvent of bonding agent(interlayer resin insulator).

[0149] The substrate 10 shown in the process (B) is washed with waterand is then dried up. Thereafter, the substrate 10 is subjected todegreasing under the acidic condition, soft-etching, processing with acatalyst solvent including palladium chloride and organic acid to obtainPd catalyst, activation and the plating in the non-electrolytic platingbath to form the recessed and projected layers (rough surface) ofNi—P—Cu alloy in the thickness of 2.5 μm at the surface of the copperconductive bodies 14 a, 14 b, target mark 11 and a via hole pad.

[0150] Thereafter, the substrate 10 is washed with water is then soakedinto the non-electrolytic tin plating bath consisting of tin fluorideboron-thioharnstoff acid solution in the temperature of 50° for an hourto form a tin replacement plating layer in the thickness of 0.3 μm atthe surface of the Ni—Cu—P alloy rough surface.

[0151] As shown in the process of FIG. 4(C), the bonding agent is coatedon the substrate 10 using a roll coater, it is then left for 20 minutesunder the horizontal condition. Then, the substrate is dried up for 30minutes at the temperature of 60° C. to form a bonding agent layer 16 inthe thickness of 50 μm. Thereafter, it is then heated at the temperatureof 170° C. for five hours to harden the bonding agent layer 16. Thisbonding agent layer 16 has light transmitting property. Thereby, thetarget mark 11 covered with the bonding agent layer 16 can be recognizedeasily with the CCD camera 82.

[0152] Thereafter, the substrate 10 is placed on the X-Y table 80 shownin FIG. 1 and the target mark 11 formed on the substrate 10 as explainedabove is measured with the CCD camera 82. Thereby, after measuring andcorrecting the deviation of the substrate 10, the pulse beam is appliedto the substrate from the laser oscillator 60 to form the hole 20 forvia hole to the bonding agent layer 16 on the substrate (refer toprocess (D)).

[0153] Namely, the boring process is conducted with the structure ofthis embodiment having formed the optical system using a condenser lens92, a collimator lens 94 and tellurium 94 as the non-linear opticalcrystal.

[0154] An output from the CO₂ laser oscillator 60 is 5000 W and pulsetime is 1 μsec. A harmonic wave output has the peak level of 1600 W andthe conversion efficiency has been 32%. Here, radiation energy has beenset to 0.8 mJ.

[0155] In this embodiment, the second harmonic wave laser beam of 5.3 μmis radiated through the bonding agent layer (interlayer resin insulator)16 in the thickness of 50 μm to expose the bottom section (internallayer copper patterns 14 a, 14 b) in order to form the hole 20 in thedepth of 50 μm. Moreover, a small via hole having the upper diameter ofhole 20 (aperture diameter) of 40 μm can be obtained.

[0156] As explained above, a fine and deep hole can be bored byutilizing the laser beam wavelength of 5.3 μm which has been obtained bymodulating the laser beam of the low cost CO₂ laser source to theshortened wavelength.

[0157] Explained here is the result of testing in formation of the viahole bored to the bonding agent layer 16 of 50 μm by radiating the laserbeam under the setting that diameter of mask 62 is 0.6 mm and radiationenergy is 0.4 mJ by structuring an optical system, for the purpose ofcomparison without use of the condenser lens, collimator lens ortellurium. In this case, an output from the CO₂ laser is 5000 W andpulse time is 1 μsec. An output of harmonic wave has the peak level of1600 W and wavelength is 10.6 μm.

[0158] The upper diameter of the hole formed for the testing is 40cm,the depth of hole is 30μm and it is impossible to expose the bottomsection (internal layer copper patterns 14 a, 14 b) passing through thebonding agent layer 16 of 50 μm.

[0159] When the radiation energy is increased up to 0.8 mJ in the sameoptical system, it has been realized to expose the bottom sectionpassing through the bonding agent layer 16 in the thickness of 50 μm,but the upper diameter of hole is 60 μm and the diameter of aperture isextended.

[0160] As explained above, when the wavelength is 10.6 μm, a hole can bebored through the bonding agent layer by increasing the output, but thehole diameter is also extended. Moreover, when the output is reduced,the hole diameter can be reduced but the laser output cannot betransmitted through the bonding agent layer and the upper layer cannotbe connected to the lower layer.

[0161] In this embodiment, since the target mark 11 is formed of copper,it assures high reflectivity and can be read easily by the CCD camera82. Moreover, since copper does not allow transmission of light beam,the positioning mark can be recognized with a silhouette and can be readeasily with the CCD camera 82. In this embodiment, copper is used fortarget mark 11, but other various kinds of metal conductors which alsoassure higher reflectivity and do not allow transmission of light beamcan be used in place of copper.

[0162] Moreover, since the target mark 11 is formed simultaneously withthe conductive circuit (internal layer copper patterns 14 a, 14 b), itis not required to additionally provide the target mark forming process.

[0163] Subsequently, a multilayer printed wiring board manufacturingmethod will be explained. In this embodiment, 5000 holes are bored atrandom on the substrate (500 mm×500 mm) with the shortened wavelengthlaser beam. Here, as explained above, the scanning area of thegalvano-mirror is 30×30 mm and the positioning velocity is 400points/sec in the scanning area. On the other hand, the number of stepareas of the X-Y table is 298 (17×17). Namely, the laser process iscompleted by repeating the movement of 30 mm in the X direction 17 timesand the movement of 30 mm in the Y direction 17 times. The movingvelocity of the X-Y table 80 is 15000 mm/min. Meanwhile, the recognizingtime of the four target marks 11 by the CCD camera 82 is 9 secondsincluding the moving time of the table 80. When the substrate 10 isprocessed by such manufacturing apparatus, the processing time has been269.5 seconds.

[0164] The substrate 10 having formed the holes 20 is soaked intochromium acid for one minute to dissolve the epoxy resin particles inthe inter-resin layer insulator in order to obtain rough surface of theinter-resin layer insulator 16 shown in the process (E). Thereafter, thesubstrate is soaked into the neutralizing solution (manufactured bySHIPLEY Corp.) and is then washed with water.

[0165] The substrate 10 having conducted the rough surface formingprocess is given the palladium catalyst (ATOTECH Corp.) to give thecatalyst core to the bonding agent layer 16 and the hole for via hole20.

[0166] Here, liquid resist is prepared. Oligomer given thephotosensitivity (molecular weight of 4000) obtained by acrylic processfor the epoxy group of 25% of the cresol novolac type epoxy resin(produced by Nippon Kayaku Co., Ltd.: Bland name EOCN-103S) dissolvedinto DMDG, an imidazole hardening agent (manufactured by ShikokuChemicals Corp.: Bland name 2PMHZ-PW), acrylic isocyanate (manufacturedby Toagosei Co., Ltd.: Bland name Alonix M215), benzophenone as thephoto-starting agent (manufactured by Kanto Chemical Co., Inc.) andMichler's ketone as the photo-sensitivity amplifying agent (manufacturedby Kanto Chemical Co., Inc.) are kneaded using NMP in the followingcomposition. Then these are adjusted to the viscosity of 3000 cps with ahomodisper stirrer and are then kneaded with three rolls to obtain theliquid resist. Resin composition; photosensitiveepoxy/M215/BP/MK/imidazole=100/10/5/0.5/5

[0167] As shown in the process (F) of FIG. 5, the liquid resist obtainedabove is coated to both surfaces of the substrate 10 having completedthe process to give the catalyst core using a roll coater. It is thendried up at the temperature of 60° C. for half an hour to form theresist layer 24 in the thickness of 30 μm.

[0168] Thereafter, after the non-removing area of the resist layer 24 isexposed by the photo-etching or radiation of small output laser, theresist layer is dissolved by DMTG as shown in the process (G) to form,on the substrate 10, the resist for plating 26 where the pattern 26 b toform the conductive-circuit pattern 26 a and target marks is eliminated.Moreover, the resist is exposed with ultra-high pressure mercury lamp inthe energy of 1000 mJ/cm² for an hour at the temperature of 100° C.Thereafter, the substrate is heated for 3 hours at 150° C. to formpermanent resist on the interlayer insulator (bonding agent layer) 16.

[0169] The substrate 10 having formed the permanent resist 26 as shownin the process (H) is subjected to the pre-plating process (in moreconcrete, process by sulfuric acid and activation of catalyst core) inadvance. Thereafter, the non-electrolytic copper plating 28 in thethickness of about 15 μm is precipitated to the resist non-forming areaby the non-electrolytic plating in the non-electrolytic copper platingbath to form the external layer copper pattern 30, via hole 32, andtarget mark 111. Thereby, a conductive layer is formed by the additivemethod.

[0170] The processes explained above are repeated to further formanother conductive layer by the additive method. In this case, an erroris measured with the CCD camera 82 using the target mark 111 formed onthe interlayer insulator (bonding agent layer) 16 and the hole for viahole is formed by laser. By building up the wiring layers, a multilayerprinted wiring board of six layers can be formed.

[0171] Subsequently, a structure of the manufacturing apparatus inrelation to the modification example of the first embodiment will beexplained. In the profile explained above by referring to FIG. 1,tellurium crystal 94 is arranged at the outside of the CO laseroscillator 60 formed by sealing the CO₂ gas between the anti-reflectionmirror 60B and the partial reflection mirror 60A Meanwhile, in thesecond embodiment, the CO₂ laser oscillator 160 is provided, by sealingthe CO₂ gas, between the tellurium crystal 194 and the anti-reflectionmirror 160B. Namely, the tellurium crystal 194 is arranged within theCO₂ laser oscillator 160. The tellurium crystal 194 is structured topartially reflect with the surface opposed to the anti-reflection mirror160B to pass only a part of the energy excited by the CO₂ gas like thepartial reflection mirror 60A in the profile shown in FIG. 1.

[0172] In the non-linear type optical crystal such as tellurium crystal,etc., since the conversion efficiency to harmonics is higher when a highoutput laser beam is incident, a high output laser beam in the CO₂ laseroscillator 160 is incident to the tellurium crystal to realize higherefficiency of the conversion to harmonics.

[0173] In the embodiment explained above, a galvano-head is used as thescanning head, but a polygon mirror may alternatively be employed. Inaddition, the laser radiating position can be adjusted by moving the X-Ytable without use of the scanning head.

[0174] In the above embodiment, the wavelength of CO₂ laser is doubledby one tellurium crystal, but it is also possible to increase the laserwavelength fourfold by providing the tellurium crystal in two stages.Moreover, the CO₂ laser is used as the laser oscillator, but it is alsopossible in the present invention to use the harmonics of various lasersources such as argon, etc. Here, the wavelength of laser beam must be360 nm or less or 3000 nm or more to bore the holes to the interlayerresin insulator. Namely, the laser beam in the wavelength larger then360 nm and smaller than 3000 nm is used to eliminate generation of headwhen the laser passes the resin. Therefore, when the wavelength isdoubled, the laser source of the wavelength smaller than 720 nm andlarger than 6000 nm must be used. Moreover, when the wavelength isincreased up to four times, the laser source of the wavelength smallerthan 1440 nm and larger than 12000 nm must be used.

[0175] In addition, in the first embodiment explained above, telluriumis used as the non-linear optical crystal, but various kinds ofnon-linear optical crystal may be used so long as the phase matchingwith the laser beam can be attained and such optical crystal allowstransmission of the laser beam from 10 μm to 5 μm. For example,gallium-selenium GaSe, antimony sulfide Ag3SBS3, arsenic sulfideAg3ASS3, mercury sulfide HgS and selenium Se, etc. can be used.

[0176] Moreover, as a work piece to be processed, a multilayer printedwiring board is used but the work piece is not limited thereto.

[0177] The second embodiment of the present invention will be explainedwith reference to FIG. 7 to FIG. 11. FIG. 7 shows the multilayer printedwiring board manufacturing apparatus in relation to the secondembodiment of the present invention.

[0178] In the second embodiment, the CO₂ laser oscillator 260 in thewavelength of 10.6 μm is used as the laser source. The light beamemitted from the laser oscillator 260 is sent to the galvano-head viathe transfer mask 262 in order to make clear the focal point on thesubstrate.

[0179] The scanning head 270 is formed of a galvano-mirror formed of aset of the galvano-mirror 274X for scanning the laser beam in the Xdirection and the galvano-mirror 274Y for scanning the beam in the Ydirection. These mirrors 274X, 274Y are driven by the control motors272X, 272Y. The motors 272X, 272Y adjust the angles of the mirrors 274X,274Y according to the control command from the computer to be explainedlater and also transmit the detecting signal from the built-in encoderto the computer side.

[0180] The scanning area of the galvano-mirror is 30×30 mm. Moreover,the positioning speed of galvano-mirror is 400 points/sec in thescanning area. The laser beam is scanned in the X-Y directions via acouple of galvano-mirrors 274X, 274Y to pass the f-θ lens 276 and thenreach the bonding agent layer described later of the substrate 210 toform a hole 220 (aperture) for via hole.

[0181] The substrate 210 is placed on the X-Y table 280 moving in theX-Y directions. As is explained above, since the scanning area of thegalvano-mirror of each galvano-head 270 is 30 mm×30 mm and the substrate210 of 500 mm×500 mm is used, the step area of the X-Y table 280 is 289(17×17).

[0182] In the manufacturing apparatus, the CCD camera 282 is provided tomeasure the position of the target marks (positioning marks) 211 aarranged at the four corners of the substrate 210 and correct an errorin view of starting the processing.

[0183] A structure of the X-Y table 280 of this embodiment will beexplained in further detail by referring to FIG. 7 and FIG. 8. FIG. 8 isa cross-sectional view along the line A-A of the X-Y table 280 shown inFIG. 7.

[0184] As shown in FIG. 7, a rectangular aperture 280 a of 30 mm×8 mm isprovided to the area corresponding to the positioning mark 211 a of theprinted wiring board 210 when the printed wiring board 210 is placed atthe four corners of the X-Y table 280. As shown in FIG. 8, a socket 286is engaged with respective aperture 280a. The socket 286 is connected tothe cable 283 wired at the inside of the X-Y table 280 and this cable283 is connected to the connector 281 provided at the end part of theX-Y table 280. This connector 281 is further connected to the cable 290from the external power supply. Connection with the external powersupply may also be realized through slide contact method, in addition touse of cable of this embodiment. In the socket 286, four LEDs 288conforming to the specification No. HP-HLMP-2685 (Stanley Electric Co.,Ltd. H-3000-L, Sharp Corp. GL5-UR-3K, etc.) are fixed. The aperture 280a is provided with a transparent or semi-transparent glass or acryliccover 289 and thereby the LED 288 may be protected if the laser beam iserroneously radiated. At the lower side of the X-Y table 280, the Xdrive motor 284X for driving in the-X direction and Y drive motor 284Yfor driving in the Y direction are arranged. In the X-Y table 280 ofthis embodiment, a groove and a hole (not illustrated) are provided forvacuum absorbing and fixing the substrate to the surface other than thatcorresponding to the light source.

[0185] Explanation of the control mechanism of the manufacturingapparatus is not repeated here because it is similar to that of thefirst embodiment explained above.

[0186] Here, the processing data generating process by the computer 250of the second embodiment will be explained. The process by the computer250 is similar to that of the first embodiment described above withreference to FIG. 3 and therefore it will be explained with reference toFIG. 3 and FIG. 9. FIG. 9(B) is an enlarged cross-sectional view of theaperture 280 a of the X-Y table 280 shown in FIG. 8. FIG. 9(A) is a planview of the aperture 280 a viewed from the side of the CCD camera 282.

[0187] The computer 250 first drives the X-Y table 280 to the positionof the CCD camera 282 to move the target mask 211 a (first process shownin FIG. 3). The LED 288 is caused to emit the light to pass through theBT resin substrate 210 (refer to FIG. 9(B)) to generate silhouettes ofthe target mark 211 a on the substrate surface side and of the targetmark 211 b of the substrate rear surface side (refer to FIG. 9(A)). TheCCD camera 282 recognizes the silhouettes and picks up the positions ofthe four target marks 211 a of the substrate 210 (refer to FIG. 7) tomeasure the errors such as deviation in the X direction, deviation inthe Y direction, compression of substrate, and a rotating amount (secondprocess). In order to correct the errors measured, an error data isgenerated (third process). The four target marks 211 b are picked up toprocess the rear surface side of the substrate 211. The desirable shapeof the target mark is circular shape in which the center point can beextracted easily by the computer.

[0188] Subsequently, the computer 250 corrects the hole coordinate dataconsisting of the coordinates of the processing holes with the errordata generated by the third process to generate the actual processingdata consisting of the coordinates of the holes to be bored actually(fourth process). On the basis of the actual processing data, thescanning head data for driving the galvano-head 270 is generated (fifthprocess), the table data for driving the X-Y table 280 is generated(sixth process), and the laser data of the timing for oscillating thelaser 260 is generated (seventh process). This data is temporarilystored in the memory section 252 and actual boring process is executedby driving t he X-Y table 280, laser 260, and galvano-head 270 based onthis data.

[0189] Thereafter, the manufacturing process of a multilayer printedwiring board by utilizing the multilayer printed wiring board of thesecond embodiment of the present invention will be explained withreference to FIG. 10 and FIG. 11.

[0190] First, using, as the starting material, the copper clad laminatedplate 210 a in which the copper foil of 18 μm is laminated on bothsurfaces of the substrate 210 consisting of transparent orsemi-transparent glass epoxy or BT (bismaleimidetriazine) of 500×500 mmin the thickness of 1 mm shown in the process (A) of FIG. 10, theinternal layer copper patterns 214 a, 214 b, target mark 211 a forprocessing the substrate surface and target mark 211 b for processingthe rear surface are formed on both sides of the substrate 211 byetching the copper foil into the pattern by the ordinary method as shownin FIG. 10(B).

[0191] The substrate 210 shown in FIG. 10(B) is washed with water and isthen dried up. The substrate 210 is then subject to the degreasingprocess in the acid for the soft etching purpose. It is then processedby the catalyst solvent consisting of palladium chloride and organicacid. Thereby, it is given the Pd catalyst and activated. Thereafter, itis subject to the plating in the non-electrolytic plating bath to formthe recessed and projected layer (rough surface) of Ni—P—Cu alloy in thethickness of 2.5 μm on the surface of the copper conductors 214 a, 214b, target marks 211 a, 211 b and via hole pad.

[0192] The substrate is then washed with water and is then soaked intothe non-electrolytic tin plating bath consisting of tin borofluoridethiourea for an hour at the temperature of 50° C. to form a tinreplacement plating layer of 0.3 μm in thickness at the surface of theNi—Cu—P alloy rough surface.

[0193] As shown in the process (C), the bonding agent is coated on thesubstrate 210 using a roll coater, it is then left for 20 minutes underthe horizontal condition. Then, the substrate is dried up for 30 minutesat the temperature of 60° C. to form the bonding agent layer 216 of 50μm in thickness. Thereafter, the bonding agent layer 216 is hardened byheating process for 5 hours at 170° C. in the heating furnace. Thisbonding agent layer 216 has a light transmitting property. Thereby, thetarget marks 211 a, 211 b covered with this bonding agent layer 216 canbe recognized easily with the CCD camera 282.

[0194] Thereafter, the substrate 210 is placed on the X-Y table 280shown in FIG. 7 and the substrate 210 is fixed on the X-Y table 280 byvacuum absorption through the grooves and holes provided on the X-Ytable 280. Then, the target marks 211 a formed at the four corners ofthe substrate 210 as mentioned above are measured with the CCD camera282 and deviation of the substrate 210 is measured and corrected.Thereafter, the pulse beam of 50 μsec is applied in the output of 400 Wfrom the laser oscillator 260. This light beam is used to form a hole220 for via hole to the bonding agent layer 216 of the substrate (referto process (D)).

[0195] In this embodiment, since copper which does not allowtransmission of light beam is used for the target marks 211 a, 211 b,the positioning mark can be recognized easily and can be read easilywith the CCD camera 282 by means of the silhouettes. In this embodiment,copper is used for the target marks 211 a, 211 b, but the other variousmetal conductors which also do not allow transmission of light beam canalso be used.

[0196] Moreover, since the target marks 211 a, 211 b are formedsimultaneously with the conductive circuit (internal layer copperpatterns 214 a, 214 b), it is not required to additionally provide theprocess to form the target marks.

[0197] In this embodiment, 5000 holes are bored at random on thesubstrate (500 mm×500 mm). Here, as explained above, the scanning areaof the galvano-mirror is 30×30 mm and the positioning speed is 400points/sec within the scanning area. On the other hand, the number ofstep areas of the X-Y table 280 is 289 (17×17). The moving speed of theX-Y table 280 is 15000 mm/min. Meanwhile, the recognizing time of thefour target marks 211 a, 211 b by the CCD camera 282 is 9 secondsincluding the moving time of the table 280.

[0198] When the substrate 210 is manufactured with this manufacturingapparatus, the-processing time is 269.5 seconds.

[0199] The substrate 210 having formed the holes 220 is soaked intochromium acid for one minute to dissolve the epoxy resin particles inthe inter-resin layer insulating layer to form the layer 216 having therough surface as shown in the process (E). Thereafter, the substrate issoaked into the neutral solution (SHIPLEY Corp.) and then it is washedwith water.

[0200] The catalyst core may be given to the bonding agent layer 216 andhole 220 for via hole by giving the palladium catalyst (ATOTECH Corp.)to the substrate 210 with the rough surface forming process completed.

[0201] As shown in the process (F) of FIG. 11, the liquid resist likethat in the first embodiment is coated with a roll coater on bothsurfaces of the substrate 21 with the catalyst core giving processcompleted and it is then dried up for 30 minutes at 60° C. to form theresist layer 224 of 30 μm in thickness.

[0202] Thereafter, the non-removing section of the resist layer 224 isexposed by the photo etching or laser radiation of a small output andthen the resist layer is dissolved by DMTG as shown in the process (G)to form the resist 226 for the plating on the substrate 210 where thepattern 226 b to form the conductive circuit 226 a and target marks iseliminated. Then, the substrate is exposed with an ultra-high pressurelamp in the energy of 1000 mJ/cm². Moreover, the substrate 210 is heatedfor 1 hour at 100° C., then 3 hours at 150° C. to form the permanentresist 226 on the interlayer insulating layer (bonding agent layer) 216.

[0203] As shown in the process (H), the pre-processing (specifically,process by sulfuric acid and activation of catalyst core) is executed tothe substrate 210 on which the permanent resist 226 is formed.Thereafter, non-electrolyte copper plating 228 in the thickness of 15 μmis precipitated on the resist non-forming section by thenon-electrolytic plating in the non-electrolytic copper plating bath toform the external layer copper pattern 230, via hole 232 and targetmarks 211 a′, 211 b′ in view of forming the conductive layer by theadditive method.

[0204] By repeating the processes explained above, one more conductivelayer is formed by the additive method. In this case, as shown in FIG.9(C) and FIG. 9(D), an error is measured with the CCD camera 282 and thehole for via hole is formed by laser beam by use of the surfaceprocessing target marks 211 a′ and the rear surface processing targetmark 211 b′ formed on the interlayer insulating layer (bonding agentlayer) 216. The multilayer printed wiring board of four or more layerscan be formed by building up the wiring layers as explained above.

[0205] The third embodiment of the present invention will be explainedwith reference to FIG. 12 to FIG. 17.

[0206]FIG. 12 shows a multilayer printed wiring board manufacturingapparatus in relation to the third embodiment of the present invention.

[0207] In this embodiment, the CO₂ laser oscillator 360 is used as thelaser source. The light beam emitted from the laser oscillator 360 isincident to a beam splitter 364 via the transfer mask 362 in order tomake clear the focal point on the substrate. In the beam splitter 364,the incident light is distributed by 1:1 in the power ratio and is thentransmitted to the side A galvano-head (scanning head) 370A and to theside B galvano-head (scanning head) 370B through reflection by themirror 366. As the beam splitter, those combining a plurality sets ofthe prisms and those obtained by arranging a multilayer film onzinc-selenium (ZnSe) may be used.

[0208] The side A galvano-head 370A and side B galvano-head 370B arerespectively formed of a set of galvano-mirrors consisting of thegalvano-mirror 374X for scanning the laser beam in the X direction andthe galvano-mirror 374Y for scanning the beam in the Y direction, andthese mirrors 374X, 374Y are driven by the control motors 372X, 372Y.The motors 372X, 372Y adjust the angles of the mirrors 374X, 374Y andtransmit the detecting signal from the built-in encoder to the computerside according to the control command from the computer to be describedlater.

[0209] The scanning area of the galvano-mirror is 30×30 mm and thepositioning speed of the galvano-mirror is 400 points/sec in thescanning area. The distance between the side A galvano-head 370A andside B galvano-head 370B is set to 250 mm interval which is a half ofthe substrate (500 mm×500 mm) for multiple chamfering in order toimprove the efficiency of substrate processing. The laser beam isscanned in the X-Y directions via a couple of galvano-mirrors 374X, 374Yand then passes through the f-θ lens 376 and then reaches the bondingagent layer of the substrate 310 to be explained later to form the hole(aperture) for the via hole.

[0210] The substrate 310 is placed on the X-Y table 380 moving in theX-Y directions. As explained above, since the scanning area of thegalvano-mirrors of the galvano-heads 370A, 370B is 30 mm×30 mm and thesubstrate 31 of 500 mm×500 m is used, the number of step areas of theX-Y table 380 is 289 (17×17). Namely, the laser processing is completedby repeating the movement of 30 mm in the X direction 17 times and themovement of 30 mm in the Y direction 17 times.

[0211] In the manufacturing apparatus, the CCD camera 382 is arrangedand the processing is started after measuring the positions of thetarget marks 311 arranged at the four corners of the substrate 310 andthen compensating for an error.

[0212] Subsequently, the control mechanism of the manufacturingapparatus will be explained with reference to FIG. 13.

[0213] The control apparatus is composed of a computer 350 whichreceives an input the hole coordinate data of the multilayer printedwiring board (processing data) input from the input section 354 and theposition of the target marks (positioning marks) 311 measured by the CCDcamera 382 to generate the processing data and then stores it to thememory section 352. On the basis of the processing data, the X-Y table380, laser 360 and galvano-heads 370A, 370B are driven for the purposeof actual hole boring process.

[0214] Here, the processing data generating process by the computer 350will be explained in detail with reference to FIG. 14.

[0215] The computer 350 drives the X-Y table 380 to the position of theCCD camera 382 to move the target mark 311 (first process). Errors suchas deviation in the X direction, deviation in the Y direction,compression of substrate, and an amount of rotation can be measured bypicking up the positions of the four target marks 311 with the CCDcamera 382 (second process). The error data for compensating for themeasured error is generated (third process).

[0216] Thereafter, the computer 350 corrects the hole coordinate dataconsisting of the coordinates for hole boring with the error datagenerated by the third process to generate the actual processing dataconsisting of the coordinates of the hole to be bored actually (fourthprocess). On the basis of the actual processing data, the galvano-headdata for driving the galvano-heads 370A, 370B is generated (fifthprocess), the table data for driving the X-Y table 380 is generated(sixth process), and the laser data of the timing for oscillating thelaser 360 is also generated (seventh process). This data thus generatedis-then stored temporarily in the memory section 352 and drives the X-Ytable 380, laser 360 and galvano-heads 370A, 370B on the basis of thedata for the purpose of actual hole boring process.

[0217] Generation of the galvano-data used in the fifth process will beexplained in more detail with reference to FIG. 15 showing the flowchartof this process.

[0218] At the time of manufacturing a plurality of multilayer printedwiring boards by multiple chamfering of the substrate, it may be thoughtreasonable to conduct the hole boring process with the same pattern inorder to simultaneously bore the holes of two sheets of the multilayerprinted wiring board in the same shape with the side A galvano-head 370Aand side B galvano-head 370B. However, since the positional accuracy ofthe hole boring process is 20 μm, it is required to position theadjacent two multilayer printed wiring boards of the same shape to theaccuracy of 20 μm but it is very difficult. Therefore, in thisembodiment, the holes are bored on the side A galvano-head 370Adifferently from those on the side B galvano-head 370B. The process forthis purpose is conducted by the process shown in FIG. 15 to beexplained later.

[0219] First, the computer 350 determines, from the coordinates of eachhole of the actual processing data, whether each hole should beprocessed by the side A galvano-head 370A or side B galvano-head 370B(S12). When a hole is bored with the side A galvano-head 370A (YES inthe step S14), it is also judged whether or not the hole boring processshould be conducted by the side A galvano-head 370A (step S16) at thetiming where the laser beam is supplied from the laser 360 and the holeboring process is conducted by the side B galvano-head 370B which is theother galvano-head.

[0220] Here, when the boring is not conducted (NO in the step S16), therotating positions (scanning position) of the X axis motor 374X and Yaxis motor 374Y are set (S18) to radiate the laser beam to the positiondeviated from the substrate 310, namely to the area outside theprocessing object area of the multilayer printed wiring board with thegalvano-mirrors 372X, 372Y. On the other hand, when the boring isconducted (YES in the step S16), the rotating positions (scanningpositions) of the X axis motor 374X, Y axis motor 374Y are calculated toradiate the laser beam to the coordinates positions of the target holeswith the galvano-mirrors 372X, 372Y (S20, S22). In the case ofprocessing with the side B galvano-head 370B (NO in S14), the similarprocesses (S26, S28, S30, S32) are conducted. When above processes arecompleted for the coordinates of all holes of the actual processing data(YES in S34), all processes are completed.

[0221] Subsequently, manufacturing of the multilayer printed wiringboard utilizing the multilayer printed wiring board manufacturingapparatus in relation to the third embodiment of the present inventionwill be explained with reference to FIG. 4 and FIG. 5 which have alsobeen referred to for explanation about the manufacturing process of thefirst embodiment.

[0222] The processes (A) to (C) are similar to the first embodiment andthe same explanation is not repeated here. After completion of theprocess (C), the substrate 10 is placed on the X-Y table 380 shown inFIG. 12 and the pulse beam of 50 μsec is radiated to the substrate 10 inan output of 400 W from the laser oscillator 360. This light beam formsa hole 20 for via hole to the bonding agent layer 16 of the substrate(refer to the process (D)).

[0223] In this embodiment, 5000 holes are bored at random on thesubstrate (500 mm×500 mm). Here, as explained above, the scanning areaof respective galvano-mirrors is 30×30 mm as explained above and thepositioning speed 400 points/sec within the scanning area. On the otherhand, the number of step areas of the X-Y table 380 is 289 (17×17). Themoving speed of the X-Y table 380 is 15000 mm/min. Meanwhile, therecognizing time of the four target marks 11 by the CCD camera 382 is 9seconds including the moving time of the table 380.

[0224] When the substrate 10 is processed by this manufacturingapparatus, the processing time is 134 seconds. In the manufacturingapparatus in the first and second embodiments in which only onegalvano-head is used, the processing time is 269.5 seconds. As explainedabove, the processing time can be reduced to a half in the presentinvention without changing the table size. The explanation about theprocesses (E) to (H) is not repeated here because it is similar to thatin the first embodiment.

[0225] Subsequently, the manufacturing apparatus in relation to themodification example of the third embodiment of the present inventionwill be explained with reference to FIG. 16. In the third embodimentexplained with reference to FIG. 12, two units of the galvano-heads370A, 370B are provided. Meanwhile, in the third embodiment, three unitsof the galvano-heads 370A, 370B, 370C are provided. In this example ofmodification, the light beam having the power equal to {fraction (1/3)}the power of the light from the laser 360 is supplied to the side Agalvano-head 370A via the beam splitter 364A which distributes theincident light beam in the power ratio of 1:2. Moreover, the light beamhaving the power equal to {fraction (1/3)} the power of the beam fromthe beam splitter 364A is supplied to the side B galvano-head 370B viathe beam splitter 364A which distributes the beam in the power ratio of1:1 and moreover the light beam having the power equal to {fraction(1/3)} is also supplied to the side C galvano-head 370C by means of themirror 366.

[0226] In the manufacturing apparatus of the modification example ofthis third embodiment, the hole boring time by laser can be reduced to{fraction (1/3)}. In this embodiment, three units of the galvano-headare used but it is also possible to use four or more units ofgalvano-head by adjusting the power ratio of the beams distributed bythe beam splitter.

[0227] Next, the manufacturing apparatus in relation to the othermodification example of the third embodiment of the present inventionwill be explained with reference to FIG. 17. In the third embodimentexplained with reference to FIG. 12, a unit of transfer mask 362 isarranged between the laser oscillator 360 and beam splitter 364. On theother hand, in the manufacturing apparatus of the third embodiment, thetransfer masks 362A, 362B are arranged respectively between the beamsplitter 364 and galvano-heads 370A, 370B.

[0228] In the structure of the profile explained above with reference toFIG. 12, only one transfer mask 362 is used, however, the optical pathlength up to the substrate 310 from the transfer mask 362 in the case ofthe side A galvano-head 370A is different from that in the case of sideB galvano-head 370B. Therefore, it is required that the distance up tothe side A galvano-head 370A from the substrate 310 is set differentfrom the distance up to the side B galvano-head 370B. Meanwhile, in thestructure of the other modification example shown in FIG. 17, theoptical path length up to the substrate 310 from the transfer mask 362is equal in both the case of the side A galvano-head 370A and the side Bgalvano-head 370B. Therefore, the distance from the substrate 310 to theside A galvano-head 370A can be set equal to the distance up to the sideB galvano-head 370B.

[0229] In the second and third embodiments explained above, the presentinvention is applied to a multilayer printed wiring board manufacturingapparatus, however, the present invention can also be applied to variouskinds of laser processing apparatuses. Moreover, a galvano-head is usedas the scanning head but a polygon mirror can also be used. In addition,the CO₂ laser is used as the laser oscillator, but various types oflaser may also be used.

[0230] According to the apparatus of the third embodiment, theprocessing speed can be improved by utilizing the X-Y table for placingthe single galvano-head of the related art. Namely, it is also possibleto prepare a plurality of galvano-heads and provide the laser oscillatorto these heads. In this case, the apparatus size such as the X-Y tableinevitably increases. However, in the third embodiment, since a singlelaser oscillator is used, the apparatus size is not increased.

[0231] Moreover, the area of the X-Y table can be set to the size ofonly one work piece by processing only one work piece (multilayerprinted wiring board) with two or more scanning heads and thereby theprocessing speed can be enhanced without increase in size of theapparatus.

EFFECT OF THE INVENTION

[0232] As explained above, since the shortened wavelength can berealized by modulating the wavelength of the laser source in the presentinvention, fine holes may be formed as well as via holes by use of a lowprice light source.

[0233] As explained previously, since several hundreds to severalthousands holes can be bored with radiation of laser beam while securingthe positional accuracy of the via holes in the present invention,mass-production of the multilayer printed wiring board by the laser beamcan be realized.

[0234] As explained above, since the light can always be applied fromthe lower side of the positioning marks to accurately read thepositioning marks in the present invention even when the X-Y tableitself or a drive motor is provided, the boring process by the laserbeam can be conducted with higher accuracy.

[0235] Moreover, as explained above, since a plurality of galvano-headsare provided even when only one laser source is used in the presentinvention, the boring speed can be improved without increase in size ofthe apparatus and thereby low cost laser boring can be realized.

What is claimed is:
 1. A multilayer printed wiring board manufacturingapparatus, to be used for processing a multilayer printed wiring boardhaving an interlayer resin insulator; comprising: a processing lasersource, a scanning head for deflecting the laser beam in the X-Ydirections, a camera for reading the positioning marks of a multilayerprinted wiring board, an X-Y table for placing a multilayer printedwiring board, an input section for inputting the processing data of themultilayer printed wiring board, a memory section for storing theprocessing data or the arithmetic operations result and an arithmeticoperating section, wherein the processing data is input from the inputsection and this processing data is stored in the memory section; aposition of the positioning mark of the multilayer printed wiring boardplaced on the X-Y table is measured with the camera; the inputprocessing data is corrected on the basis of the measured position ofthe positioning mark so generate the scanning head and the X-Y tabledrive data in the arithmetic section and this drive data is then storedin the memory section; and the drive data is read from the memorysection and then the X-Y table and the scanning head are controlled inthe control section and thereby the laser beam is radiated to themultilayer printed wiring board to eliminate the interlayer resin layerto form a hole for a via hole.
 2. The multilayer printed wiring boardmanufacturing apparatus according to claim 1, wherein said positioningmark is formed of a metal conductor.
 3. The multilayer printed wiringboard manufacturing apparatus according to claim 1, wherein saidpositioning mark is formed simultaneously with a conductive circuit. 4.A multilayer printed wiring board manufacturing method comprising thesteps of forming the positioning mark and interlayer insulating agentlayer on a multilayer printed wiring board; placing a multilayer printedwiring board having formed said positioning mark on the X-Y table of themultilayer printed wiring board manufacturing apparatus consisting of aprocessing laser source, a scanning head for deflecting the direction oflaser beam in the X-Y directions, a camera for reading the positioningmark of the multilayer printed wiring board, an X-Y table for placingthe multilayer printed wiring board, an input section for inputting theprocessing data of the multilayer printed wiring board, a memory sectionfor storing the processing data or the arithmetic operations result andan arithmetic operating section, and inputting the process log data tothis manufacturing apparatus: measuring the position of the positioningmark of the multilayer printed wiring board with the camera, correctingthe input processing data based on the measured positioning markposition to generate the scanning head and the X-Y table drive data inthe arithmetic operating section and then storing this drive data in thememory section; and reading the drive data form the memory section tocontrol the X-Y table and the scanning head in the control section andradiating the laser beam to the multilayer printed wiring board toeliminate the interlayer resin layer to form a hole for a via hole.
 5. Amultilayer printed wiring board manufacturing apparatus comprising aprocessing laser source, harmonic wave generating means for converting alaser beam oscillated from said processing laser source to a shortenedwavelength beam of a second harmonic wave, wherein said harmonic wavegenerating means is a non-linear optical crystal which reflects theprocessing laser to the harmonic wave emitting side and gives theretothe function to transmitting harmonic wave, and a scanning head fordeflecting a direction of the laser beam in X-Y directions or an X-Ytable for displacing a position of a multilayer printed wiring board,wherein a wavelength of said processing laser source is between 720 nmand a minimum wavelength of the laser source, or between 6000 nm and amaximum wavelength of the laser source, and said processing laser sourceforms a via hole exposing a conductive in an interlayer resin.
 6. Themultilayer printed wiring board manufacturing apparatus according toclaim 5, wherein said non-linear optical crystal is formed of a materialselected from tellurium, gallium-selenium, antimony sulfide, arsenicsulfide, mercury sulfide and selenium.
 7. A laser processing apparatuscomprising a processing laser source, harmonic wave generating means forconverting a laser beam oscillated from said processing laser source toa shortened wavelength beam of a second harmonic wave, wherein saidharmonic wave generating means is a non-liner optical crystal whichreflects the processing laser to the harmonic wave emitting side andgives thereto the function to transmitting harmonic wave, and a scanninghead for deflecting a direction of the laser beam to X-Y directions oran X-Y table for displacing a position of a work piece to be processed,wherein a wavelength of said processing laser source is between 720 nmand a minimum wavelength of the laser source, or between 6000 nm and amaximum wavelength of the laser source, and said processing laser sourceforms a via hole exposing a conductive in an interlayer resin layer. 8.A multilayer printed wiring board manufacturing apparatus, to be usedfor processing a multilayer printed wiring board having an interlayerresin insulator, comprising: a processing laser source, a scanning headfor deflecting the laser beam in the X-Y directions, a camera forreading the positioning marks of a multilayer printed wiring board, anX-Y table for placing a multilayer printed wiring board, an inputsection for inputting the processing data of the multilayer printedwiring board, a memory section for storing the processing data or thearithmetic operations result and an arithmetic operating section,wherein said X-Y table is provided with a light source embedded to thearea corresponding to the positioning mark of the multilayer printedwiring board.
 9. A multilayer printed wiring board manufacturingapparatus, to be used for processing a multilayer printed wiring boardhaving an interlayer resin insulator, comprising a processing lasersource, a scanning head for deflecting the laser beam in the X-Ydirections, a camera for reading the positioning marks of a multilayerprinted wiring board, an X-Y table for placing a multilayer printedwiring board, an input section for inputting the processing data of themultilayer printed wiring board, a memory section for storing theprocessing data or the arithmetic operations result and an arithmeticoperating section, wherein said X-Y table is provided with a lightsource embedded at the area corresponding to the positioning mark of themulti layer printed wiring board; the processing data is input from theinput section and this processing data is stored in the memory section;silhouette generated when the light beam from the light source of theX-Y table is shielded by the positioning mark is read by the camera tomeasure the position of the positioning mark of the multilayer printedwiring board placed on the X-Y table; the data for driving the scanninghead and the X-Y table is generated from the measured position and theinput processing data in the arithmetic operating section, and the drivedata is stored in the memory section; and the drive data is read fromthe memory section and then the X-Y table and the scanning head arecontrolled in the control section and thereby the laser beam is radiatedto the multilayer printed wiring board to eliminate the interlayer resinlayer to form the hole.
 10. The multilayer printod wiring boardmanufacturing apparatus according to claim 8 or 9, wherein said lightsource is an LED.
 11. A multilayer printed wiring board manufacturingmethod utilizing a manufacturing apparatus comprising a processing lasersource, a scanning head for deflecting the direction of laser beauty inthe X-Y directions, a camera for reading the positioning mark of themultilayer printed wiring board and an X-Y table for placing themultilayer printed wiring board to be provided with a light sourceembedded to the area corresponding to the positioning mark of themultilayer printed wiring board, comprising the steps of: forming thepositioning mark and an interlayer insulating agent layer on themultilayer printed wiring board; inputting the processing data to saidmanufacturing apparatus; reading, with a camera, a silhouette which hisgenerated when the light beam from the light source of said X-Y table isshielded by said positioning mark of the multilayer printed wiring boardplaced on the X-Y table to mcasurc the position of positioning mark ofthe multilayer printed wiring board; generating the data for driving thescanning head and the X-Y table from the measured position and saidinput processing data; and controlling the X-Y table and the scanninghead on the basis of said drive data and radiating the laser beam to themultilayer printed wiring hoard to eliminate the interlayer resin layerto form a hole.
 12. The multilayer printed wiring board manufacturingmethod according to claim 11, wherein, said light source is an LED. 13.The multilayer printed wiring board manufacturing method according toclaim 11 or 12, wherein the positioning mark of an upper layer isdeviated, when it is formed, from the positioning mark of a lower layerin the step of forming the positioning mark and the interlayerinsulating agent layer on said multilayer printed wiring board.
 14. Alaser processing apparatus comprising a processing laser source, ascanning head for deflecting the direction of laser beam to the X-Ydirections, a camera for reading the positioning mark of a work piece tobe processed, an X-Y table for placing the work piece, an input sectionfor inputting the processing data of the work piece a memory section forstoring the processing data or the arithmetic operations result and anarithmetic operating section, wherein said X-Y table is provided with alight source embedded to the area corresponding to the positioning markof the work piece.
 15. A laser processing apparatus comprising aprocessing laser source, a scanning head, for deflecting; the directionof laser beam to the X-Y directions and an X-Y table for placing a workpiece to process said work piece with the laser beam by controlling theX-Y table and the scanning head, wherein at least two or more scanningheads are provided, a beam splitter is provided between said processinglaser source and an optical path of the scanning head and the laser beamis distributed by this beam splittcr supply to each scanning head.
 16. Amultilayer printed wiring board manufacturing apparatus, to be used forprocessing a multilayer printed wiring board having an interlayer resininsulator, comprising: a processing laser source, a scanning head fordeflecting the laser beam in the X-Y directions, a camera for readingthe target marks of a multilayer printed wiring board, an X-Y table forplacing a multilayer printed wiring board, an input section forinputting the processing data of the multilayer printed wiring board, amemory section for storing the processing data or the arithmeticoperations result and an arithmetic operating section, wherein theprocessing data is input from the input section and this processing datais stored in the memory section; position of the target mark of themultilayer printed wiring board placed on the X-Y table is measured withthe camera; data to drive the scanning head and the X-Y table isgenerated from the measured position and the input processing data inthe arithmetic section and this drive data is then stored in the memorysection; and the drive data is read from the memory section and then theX-Y table and the scanning head are controlled in the control sectionand thereby the laser beam is radiated to the multilayer printed wiringboard to climiuatr the inleflayer resin layer to form the hole, saidmanufacturing apparatus being provided with at least two or morescanning heads, a beam splitter provided between said processing lasersource and an optical path of the scanning head, the beam splitterdistributing and supplying the lacer beam to each scanning head.
 17. Themultilayer printed wiring board manufacturing apparatus according toclaim 16, wherein when a hole for via hole it not bored with the otherscanning head on the occasion of forming the hole for via hole with thelaser beam via only one scanning head, the relevant other scanning headscans the area outside the processing object region of a multilayerprinted wiring board with the laser beam.
 18. The multilayer printedwiring board manufacturing apparatus according to claim 15 or 16,wherein one transfer mask is arranged between said processing lasersource and said beam splitter.
 19. A multilayer printed wiring boardmanufacturing apparatus according to claim 15 or 16, wherein a transfermask is respectively arranged between said beam splitter and eachscanning head.
 20. A multilayer printed wiring board manufacturingmethod comprising the steps of: forming a target mark on a multilayerprinted wiring board having an interlayer resin insulator; placing themultilayer printed wiring board having formed said target mark on theX-Y table of the multilayer printed wiring board, manufacturingapparatus comprising a processing laser source, at least two or morescanning heads for deflecting the direction of laser beam to the X-Ydirections, a camera for reading the target mark of the multilayerprinted wiring board, an X-Y table for placing the multilayer printedwiring board an input section for inputting the processing data of themultilayer printed wiring board, a memory section for storing theprocessing data or the arithmetic operations result and an arithmeticoperating section, and then inputting the procrssiag data to thismanufacturing apparatus; measuring, with the camera, the position of thetarget mark of the multilayer printed wiring board, generating the datafor driving the scanning heads and the X-Y table from the measuredposition and the input processing data in the arithmetic operatingsection and storing this drive data to the memory section; and readingthe drive data from the memory section and controlling the X-Y table andthe scanning heads in the control section and radiating the laser beamto the multilayer printed wiring hoard to eliminate the interlayer resinlayer to form the hole for the via hole, wherein the laser beam isdistributed by a beam sputter arranged between said processing lasersource and an optical path of the scanning head and is then suppliedsaid two or more scanning heads.